Handwriting recognition systems allow users to input handwritten data into a computer. The user writes data on an electronic tablet with a special pen, and as the user moves the pen across the tablet, the tablet displays lines corresponding to the path travelled by the pen. These lines appear as they are written until the pen is lifted from the tablet. After a predetermined time period, the handwritten lines are recognized as letters, symbols, numbers, or graphical shapes.
Handwriting recognition systems use algorithms to map handwritten data to recognizable symbols. Typically, these systems store a prototype for each symbol that can be recognized. A prototype is a "picture" of a handwritten symbol. Recognition systems use recognition algorithms to map handwritten data to a prototype. When recognizing graphic objects, prior art systems use prototypes such as squares, rectangles, circles, ovals, etc. These prototypes all have a solid line style and a transparent fill pattern, i.e., they are hollow shapes. A user is not able to draw a shape and specify a format, e.g., a line style or fill pattern, for that shape at the same time. For example, when a user desires to input a shape with a line style other than solid, prior art systems require the user to go through a two-step process. The user must first draw the shape, and then, after the shape is recognized by the system, select a desired line style from a palette, menu, or dialog, or type some accelerator key sequence. Similar steps are required to input a shape with a fill pattern other than transparent.
One of the difficulties encountered when a shape and a fill pattern are drawn at the same time is being able to distinguish what lines make up the object and what lines make up the fill pattern.